The edge where a raised sidewalk or road median/central reserve meets a street or other highway is referred to as a kerb & the process is called Kerb Edging.
Edging a lawn or driveway gives it a crisp, clean appearance and helps the eye establish the border between the lawn or flower beds and the tougher aspect of your driveway’s concrete, stone, or blacktop surface.
Kerbs perform several functions:
- Maintaining the carriageway edge to prevent “spreading” and structural failure.
- serving as a barrier or boundary between road traffic and pedestrians or verges
- Providing a physical ‘check’ to keep cars from leaving the roadway.
- Creating a canal via which surface water can drain.
There are several varieties of road kerbs used in the United Kingdom and Ireland. Natural stone, such as granite, was popular 50 years ago, but it has since been surpassed by pre-cast concrete. Steel kerbs have been utilized to cope with the continual overrunning of cars in confined regions experiencing unusually heavy traffic, such as town or city centres, and extruded kerb lines are often employed on our motorways and dual carriageways.
Types of kerbs
There are four types of kerbs:
- Low or Mountable Kerbs.
- Low-Speed Barrier or Urban Parking Kerbs.
- High-Speed Barrier Kerbs.
- Submerged Kerbs.
Low or Mountable Kerbs.
- Low or mountable kerbs are also referred to as class I kerbs. The major purpose of the kerbs is to keep vehicles inside their lane.
- The height of this type of curb is low to allow the motorist to approach the shoulder area with less trouble.
- This style of kerb is useful for longitudinal drainage systems, and its height ranges from 70 to 80 mm.
Low-Speed Barrier or Urban Parking Kerbs
- Class II kerbs are sometimes known as low-speed barriers or urban parking kerbs.
- To the footpath to prevent slow-moving or parked cars from encroaching.
- Severe emergency vehicles can ascend and park on the footpath or shoulder.
- The height of this sort of curb is 150 to 200 mm to reduce tyre scratching.
High-Speed Barrier Kerbs
- Class III kerbs are another name for high-speed barrier kerbs. High-speed barrier kerbs are utilized on bridges, mountains, and other vital paths.
- The height of these kerbs ranges from 230 to 450 mm or more.
Submerged Kerbs
- The submerged kerb is often referred to as a class IV kerb. This style of kerb is frequently found on country roads between the edges and shoulders.
- To give the granular base course and flexible pavements lateral support.
- It is delivered in the form of standing bricks or concrete blocks.
Tools Required for Laying Edging Kerbs
- A mixing shovel
- To ensure that the edging is plumb, a level is needed.
- String line with canes, bars, or pegs for line support.
- For pounding stones into position, use a mallet or a builder’s hammer.
Materials Required
- Kerb stones
- Ballast (mixed aggregate) or alternatively small stone and building sand
- Portland or fly ash cement
Process to lay kerb Edging
Dig a trench
Make a trench 8″ (200 mm) broad and 7″ (175 mm) deep. A 2″ to 3″ (50 mm to 75 mm) concrete bed is suitable for installing light edging kerbs, allowing 2″ to 3″ of the edging (for 7″ edging) to protrude above the surface when laid on top of the bed; however, the depth of the trench can be adjusted to vary this.
Mix the Kerb for Bedding the Edging
Use a C20 general purpose mix, which consists of one part cement, four parts stone, and two parts sand. (These are volume proportions, not weight proportions.) A single mix with a small cement mixer will yield roughly a wheelbarrow full of concrete, enough to bed three 3 foot long (about 1 m) kerbs. Concrete should be stiffly mixed with as little water as possible to maintain edging stones without being forced out from beneath.
Laying
To map out the line of your edging, use a taut string line. Before putting your blocks, run cement along this line.
Use a paving mallet to smash your edge blocks into place and at the appropriate height for your driveway, patio, or walkway.
Make a 75mm wide haunching around the perimeter of your edging block. This will secure your driveway, patio, or pathway.
Edging blocks with insufficient haunchings increases the danger of damage to the main driveway area. The haunching should extend halfway up the edging block. To get a decent cosmetic finish, smooth the haunching.
Curved Lines
To verify the height of curved edges, use a spirit level to measure back to the taut line. To accommodate curved edgings, blocks may need to be trimmed.
To begin, lay out your edging and use chalk to define the form needed on the block.
To form the blocks, use a saw or a block splitter.
Lay from this point using the same way as you would for curved edging.
Making an arc is the simplest approach to making a curved edging. To do so, locate the centre of the intended paved area and stake it in the ground. To make a consistent and flowing curving edging, use a single length of thread from this stake to measure out the placement of each block.
Flat Top Path Edging
Flat top path edgings can be used to separate a paved region from garden soil or grass, as well as keep plants off the walk or patio. There are three heights of flat top-edging: 150mm, 200mm, and 250mm. Place these edges on a concrete bed of 100-150mm and haunch three-thirds of the way upside the edging ‘outside’. The edging will be pressed into the patio or pathway by the haunching.
Conclusion
If we summarized all this process; Kerbs are supported by a concrete bed underneath and haunching or supporting concrete at the back. Because the majority of the pressure will be from cars and human activities on the driveway surface, the stones will not be pushed backwards into flowerbeds or the lawn. You may also provide support to the front with concrete or backfill with stone.
It is suggested to always hire a professional for these types of services. Advanced Driveway Solutions provide the best services in Blackpool, Flyde or Barrow in Furness.
